1. Field of the Invention
The present invention relates to a warning device.
2. Description of Related Art
As a conventional warning device, the device disclosed in Japanese Patent Application Publication No. 2012-238185 (JP 2012-238185 A) is known. The warning device described in Japanese Patent Application Publication No. 2012-238185 (JP 2012-238185 A) finds the position of an intersection at which the course of a moving object ahead of a host vehicle intersects with the course of the host vehicle, calculates the estimated crossing-time (ECT: Estimated Crossing_Time) that elapses before the moving object arrives at the intersection position and the estimated crossing-time that elapses before the host vehicle arrives at the intersection position and, based on these estimated crossing-times, outputs a warning to alert the driver of the host vehicle to the moving object. According to such a warning device, the more distant it is from the position of intersection with a moving object to the host vehicle, the earlier the start of warning output is, that is, the warning output is started when the ECT of the moving object is still large.
For example, at an intersection where a priority road (main road) and a non-priority road (narrow road) intersect, the host vehicle, which is going to enter the priority road from the non-priority road, should not disturb the traveling of moving objects such as other vehicles traveling on the priority road. Therefore, it is sometimes necessary to output a warning earlier than at a usual traveling time such as when traveling on a priority road. However, the warning device described above does not consider this requirement, with a possibility that a warning is not output at an appropriate time.